When PNG is the right choice
- Editing. Every time a JPG is saved it loses a little detail. A PNG can be opened and saved again and again without that loss.
- Design and slides. Design tools and presentation apps handle PNG everywhere, and it keeps fine detail and text crisp.
- An editing master. Keep one PNG as the untouched starting point, then export JPGs from it when you share.
For sharing, email or uploading, JPG is the better pick: the files are far smaller and look the same. You can switch the output format above at any time.
How the conversion works
When you drop a photo, your browser decodes the HEIC file with libheif, draws the pixels and saves them as a PNG. Every step runs inside this tab. On Safari, the browser’s own HEIC decoder is used, which is even faster.
Check it yourself. Open your browser’s developer tools, switch to the Network tab and add a photo. You’ll see the tools load once and no uploads. Once the page has loaded, you can turn off Wi‑Fi and keep going.
Questions
Is PNG better quality than JPG?
PNG is lossless: the pixels are saved exactly as decoded, with no compression artifacts. A high-quality JPG looks the same to most people, but PNG is safer when a file will be edited and saved many times.
Why is my PNG file so large?
Lossless compression can’t shrink detailed photos much, so a PNG is often several times the size of the original HEIC. Choose JPG if you only need to share or upload the photo.
Can the PNG have a transparent background?
Not automatically. Photos don’t contain transparency, so the PNG keeps the full rectangular image.
Why do the colors look slightly different?
Most iPhone photos use the wide Display P3 color space. Browsers save converted files in standard sRGB, so very saturated reds and greens can look a touch less vivid than in the Photos app. Everyday colors look the same.
Is anything uploaded?
No. Everything runs in your browser, and your files never leave your device.